Screw-cutting tool.



Patented oef. 17, |899.v

E. H. WILLIAMS. scnEw cuTTm'G TooL.

(Application med Aug. 1e, 189s.)

(No Model.)

@u j2me/@i075 UNITED STATES PATENT EEICE.

EDWIN H. WILLIAMS, OF HARTFORD, CONNECTICUT, ASSIGNOR OF ONE'- THIRD TO JOHN B. SIMONDS, OF SAME PLACE.

SCREW-CUTTING TOOL.

SPECIFICATION forming part of Letters Patent No. 635,272, dated October 1'7, 1899.

Application iiled August 16, 1898. Serial No. 688,693. (No model.)

- use in the many forms of turret-head screwlathes or other metal-working machines in which the stock and tools are fed toward each other in the same axial line during the cutting operation.

The object of my invention is to provide a device having the cutting-die formed of separable sections which will be securely and `positively held in proper alinement during the cutting operation and instantly released and separated when a predetermined length of thread has been cut, thus allowing a rapid withdrawal of the tool from the stock upon which it has been operating; further, to provide positive automatic means for operating the sections of the die both in their opening and closing movements.

To this end my invention consists in the device as a whole, in the combination of the parts, and in the details of such parts and their combination, as hereinafter described, and more particularly set out in the claims.

Referring to the drawings, Figure 1 is a plan View of the device. Fig. 2 is an end view of the parts shown in Fig. 1, looking from the left. Fig. 3 is an edge or side View. Fig. 4 is a sectional view on the line .fr 0c of Fig. l. Fig. 5 shows a plan view of a modi-v fied form of the device. Fig. 6 is an end view of the device shown in Fig. 5, looking toward the cutting-dies. Fig. 7 is a plan and end View of a portion of a metal-workin g machine, showing my improvement attached to the turret to illustrate its operation.

In the accompanying drawings the letter a denotes the base or support, terminating at one end in a hollow shank b, suitably formed to be inserted and held in a tool-holder such lathe. This support a, has near its forward tions.

end an angular slideway a, adapted to control the movement of and retain the slideblocks c c', insuring the latter against all movement whatever except in a line at right angle to the axis of the stock. A portion of the base a, between the slide-blocks and below and in the rear of the cutters, is cut away, as at CL2, allowing free egress to chip or other waste material liable to collect and clog the operation of the device. Cutter-sections d d are secured to these slide-blocks in any suitable manner, as by screws c e', the slideblocks being preferably mortised to provide a rm seat for the cutter-sections. The slideblocks, with their cutter-sections, when allowed free movement are forced apart along the slideway a. by springs ff', cooperating with a spring--plug f2. The latter being of suicient length to extend within the slideblocks acts both as a supplemental guide and stiener for theblocks. It will be readily seen from this construction and arrangement of Vthe slide-blocks and opening-springs that the instant the trip-block hereinafter described releases the slide-blocks there is absolutely nothing to prevent an instantaneous and unrestrained separation of the slideblocks and cutter-sections.

Levers g g', pivoted to the support a and having ball-and-socket connections with the slide-blocks c c', respectively, confine the latter, with the cutter-sections, to certain posi- The exact position and adjustment of the slide-blocks and cutters, however, are determined by the position of the adjustable stop-plates h h', cooperating with the tripblock 7c. These plates have a lateral adj ustment on their respective levers, slideways being provided in the levers, in which the plates. lare moved and adjusted, as by screws h2.

The inner edges of the plates are cut away,

abrupt shoulders being thus formed, as at h3.

When the cutter-sections are in their closed or cutting position, the shoulders h3 rest against the trip-block lo, a rm and rigid connection being thus formed to hold the cutters against separation.

A trip-lever t', pivoted to the support, as at i', and having an extension i, transmits the proper movements to the trip-block k through the medium of a stud lo. This trip-block 7c IOO moves in a suitable slideway formed in the support a and is normally forced forward to engage the shoulders h3 of the stop-plates by the spring i3 bearing against the trip-lever t'.

The letterl denotes the closer. It consists of a spring-pressed plug mounted within a suitable retainer in the support and provided with a cone-shaped head adapted to engage and force apart the levers g g', together' with the stop-plates, upon coming in contact with a suitable cam-surface. As will be readily seen, as soon as the stop-plates are forced apart a sufficient distance the trip-block, under the action of the spring i3, will be forced forward to engage and lie between the shoulders h3.

In the modified form of my invention shown in Figs. 5 and 6 the base or support 1 has slide-blocks 2 3 and operating-levers 4 5 mounted upon it in the same manner asin Fig. 1. The stop-plates (5 7 in this form are integral with the levers 4 5. The cutter-sections 8 9 are mounted in suitable slideways formed in the slide-blocks and are moved and adjusted by screws 10 11. Set-screws l2 13 are employed to lock the cutter-sections after they are once properly adjusted. The tripblock 14 has an extension 15 underlying the stop-plates and provided with guide-slots 1G 17. Pins 1S 19, fast in the under side of the stopplates, project within these slots, and thus form a positive guide for the levers 4 5 in their opening and closing movements.

It is obvious that in either of the forms shown cutter-sections forming dies of various sizes may be used. The attachment and adj ustlnent of these cuttersections being easily and quickly made, a device is obtained whichV maybe used for cutting threads of various sizes and of different pitch, a single device doing the work which would ordinarily require several separate and costly tools.

The operation of the device is as follows: Referring to Fig. 7, the cutter-sections being closed the hollow shank of the tool is inserted and clamped in one of the tool-holders of the turret A, which is adapted to be moved or fed toward the stock B until the required work has been performed upon said stock, then retracted and revolved until a second tool has been brought into proper position to be fed toward the stock. As the turret and tool are moved forward the stock B is rotated rapidly and as it comes in contact with the cutting-die a thread is formed upon the stock. Then a predetermined length of thread has been cut, the extension i2 of the trip-lever t' comes in contact with an adjust` able stop m, located at a iixed point on the machine. The trip-block 7a is forced from between the shoulders of the stop-plates, and the cuttersections being absolutely unrestrained as to outward movement are instantly forced apart and out of engagement with the stock, as shown in dotted outline. The turret now retracts, and during its revolution the cutter-sections now open are reset as the closer-plug Zis forced upward bya camsurface miocated on the turret-slide o. From the construction of the device as here shown it will be readily seen that the timing of the Aopening of the die may be adjusted to a nicety.

Moreoveigthe cutting-die being located at the extreme front of the device and having its cutter-sections movable in a line at right angle to the axis of the stock allows the cutting of a thread of uniform and full depth even up to a shoulder on the stock.

It is evident that other means than those shown herein may be employed to secure the instant opening of the cutter-sections, and I do not wish to limit myself to the exact means here shown, as any means for instantly releasing and opening the several sections of the die without otherwise altering their position with relation to the support will come within the scope of my invention.

I claim as my improvement- 1. In combination, in a screw-cutting tool, a rigid support, a sectional cutting-die mounted in the support and movable onlyin a line at right angle to the axis of the stock operated upon, means for effecting an instantaneous, unrestricted and direct outward movement of the sections of the die, and means independent of the opening mechanism for closing the sections of the die.

2. In combination, in a screw-cutting tool, a rigid support,a separable cutting-die mounted in the support and movable only in a line at right angle to the axis of the stock operated upon, means for rigidly locking the sections in their closed position, means for effecting an instantaneous, direct and unrestricted outward movement of the sections of the die, and means independent of the locking and opening mechanism for closing the die.

3. In a screw-cutting tool, in combination, a rigid support, a separable cutting-die having a plural number of cutter-scctions mounted in the support and movable only in a line at right angle to the axis of the stock operated upon, each independently adjustable with respect to a common locking device, a trip device adapted for locking and instantaneous releasing actions with respect to the cutter-sections, and means independent of the locking and releasing mechanism for closing the cutter-sections.

4. In combination, in a screw-cutting tool, a support, a slideway formed in the support, slide-blocks carrying cutter-sections adapted to be moved along the slideway, levers for moving the slide blocks having ball-andsocket connections therewith, and automatic means for permitting an instantaneous and unrestrained movement of the levers and appurtenant mechanism.

5. In combination, in a screw-cutting tool, a support, slide-blocks carrying cutter-sections movably mounted in the support, levers for moving the slide-blocks, atrip-block, adjustable stop-plates mounted on the levers IOO IIO

and adapted by their position to determine the position of the slide-blocks and their cutter-sections, and automatic means independent of the trip-block for forcing the levers and appurtenant mechanism to their closed position.

6. In combination, in a screw-cutting tool, a support, slide-blocks carrying cutter-sections movably mounted in the support, means for adjusting the cutter-sections, a trip-block adapted for loc-kin g and instantaneous releasing actions with respect to the cutter-sections, stop-plates adapted to engage the trip-blocks, to lock the levers and appurtenant mechanism, and means independent of the trip mechanism for forcing the cutter-sections to their closed positions.

7. In combination, in a screw-cutting tool, a support, slide-blocks movable in the support and provided with cutter-sections mounted in position to have a full and unobstructed eld of operation on their Work, means for permitting an instantaneous, direct and unrestricted movement of the slide -blocks and their cutter-sections from their Working to their open position in a line at right angle only to the axis of the stock operated upon,

and means independent of the releasing mechanism for forcing the slide-blocks and their cutter-sections to their closed positions.

8; In combination, in a screW-cutting-tool, a rigid support, slide-blocks carrying cuttersections movably mounted in the support and having movement only in a line at right angle to the axis of the stock, levers controlling the movements of the slide-blocks and having ball-and-socket connections therewith, automatic means for locking or instantaneously releasing the levers and appurtenant parts, and means independent of the locking and releasing mechanism for resetting the die.

9. 'In combination, in a screw-cutting tool, a rigid support, cuttersections movably mounted in the support, a movable trip mech- -anism adapted for locking and instantaneous releasing actions With respect to the cuttersections, and means interposed between the trip mechanism and cutter-operating mechanism for independently adjusting the several cutter-sections.

EDWIN H. WILLIAMS. Vit-nesses:

WILLIAM F. HENRY, WILLIAM I-I. BARKER. 

